Antinuclear Antibody Multiplex Utilization Across a Large Federal Hospital System: An Investigation of Ordering...

Area of Science:

• Clinical immunology
• Rheumatology
• Diagnostic testing

Background:

• Antinuclear antibody (ANA) multiplex assays are increasingly utilized in autoimmune disease diagnosis.
• Understanding the patterns of ANA multiplex test ordering is crucial for optimizing diagnostic strategies.

Purpose of the Study:

• To analyze the ordering patterns of ANA multiplex testing within a large US Department of Defense (DoD) tertiary healthcare system.
• To correlate ANA multiplex assay results with new autoimmune rheumatic disease (ARD) diagnoses.

Main Methods:

• Retrospective review of 2499 patient records with ANA multiplex assays ordered over one year.
• Exclusion of duplicate tests and patients with pre-existing ARDs.
• Analysis of clinical presentation, ordering specialty, rationale, and subsequent ARD diagnosis.

Main Results:

• ANA multiplex assays were ordered for over 100 reasons, primarily by primary care and medicine subspecialties.
• Only 1.66% of ANA multiplex assay-negative patients received a new ARD diagnosis, compared to 13.7% of positive cases.
• 97% of ordered ANA assays did not result in an ARD diagnosis.

Conclusions:

• Frequent use of ANA multiplex assays for nonspecific symptoms indicates potential overuse.
• Low yield of new ARD diagnoses suggests a need for better clinical guidelines for ANA testing.
• Implementation of strategies to refine appropriate clinical contexts for ANA testing is recommended.